Here's a 1984 ad for the Etonic Allegro running shoe featuring the "Radial Sole System" engineered by an Etonic biophysicist and his switchblade. 👟🗡️ The cliff notes version of this ad is that they contoured the heel to match how most runners strike the ground at an angle. Another interesting design concept along the lines of "less is more."
Ad info is below:
Etonic may have just sliced a minute off of your time.
The New Etonic Allegro' helps you run more efficiently, which can only mean faster times and better training.
One of our Etonic biophysicists and his knife may have changed the shape of your running forever.
After months of analyzing worn out running shoes and studying the natural motion of barefoot runners, he realized that most running shoes actually hinder the average runner's gait. So armed with the results of his research and a sharp blade, he fashioned a prototype of the Allegro—the first running shoe contoured at the heel to match the natural angle of the foot at heel strike.
Introducing the Radial Sole System.
But why a contoured heel? Because most runners strike the ground at an angle on the rear lateral quarter of their shoes. This angle of impact is determined by the radius of the subtalar joint—a complex ankle joint that allows the foot to rotate side to side. By contouring the heel to match the radius of the average subtalar joint, we created the Radial Sole System. Unlike conventional flare - or square-soled running shoes, the Allegro's revolutionary Radial Sole System allows your foot to strike the ground smoothly, which results in a more natural gait cycle. It's as if you were running barefoot.
And since your foot isn't landing on an unstable square edge or fighting an unnecessary chunk of EVA foam, you reduce the "slapping effect" often experienced with flared soles and therefore run more efficiently.
New outsole for better traction and support.
But, the Allegro's Radial Sole System is more than just a contoured heel. Its unique new outsole is a story in itself. First, the new outsole is made of tough Goodyear "Indy 500" rubber for long wear. Then, by strategically placing multiple rows of raised rubber bars, we were able to provide exceptional traction and support without adding unnecessary thickness or weight. Where traction is needed most, in the heel, on the lateral side and in the forefoot, the bars are perpendicular to the direction of motion.
Where additional support is required, particularly in the medial arch area, the bars are positioned "with" the direction of motion. The rubber nubs on the remainder of the outsole give cushioning and omni-directional traction. A smoother gait for improved efficiency. When you first start running in the Allegro, you may have to get accustomed to the sensation of improved efficiency. After all, you've been running in conventional shoes a long time. However, you'll soon develop a smoother, more natural gait that will make a marked improvement in your training. And if the Allegro can do that for your training, just think, it could cut a minute, maybe more, off your racing times.
A money-back guarantee.
Training or racing, the Etonic Allegro will make a profound difference in your performance. We believe that so strongly, we're offering it with an unconditional money-back guarantee.* So don't waste another minute, get down to your participating dealer and try out the Allegro for yourself.
Winning never felt better
See your participating dealer for details.